They see a break, but it isn't a structurally meaningful one. $500 is certainly short-term beneficial when you are making $30K--it is not enough, by at least an order of magnitude, to create long-term benefits, even if the knock-on effect of those tax cuts was not to ensure that the person making $30K a year ends up spending more than that $500 poorly replicating the government services that will be cut to pay for the top end of it.

Even setting aside all that, that these tax cuts are functionally useless except as a transfer of wealth to monied interests, they expire in ten years besides. It's a more complex problem than what a calculator can really express without losing the ability to give a Nice Shiny Number out the other end.